C2 Exhaust Pipe Heat Shields

[Michael H.]

An interesting topic came up Sunday about 63-67 front exhaust pipe heat shields. I would like to do a little research on this subject. Does anyone have what they believe to be the original shields from their car? I know that the part number changed a few times over the years but I only have 63 and 66 AIM's here.

I also know that these shields became shorter over the years. I have to assume that the latest number for 67 was also used to service all previous models.

I have a set of 63's here but examples from all the years would be needed to get some accurate results. I also have a set of reproductions that are supposed to be for 66. (much shorter than my 63's) What do the various reproductions call for as far as application?

I'll post a pic of the 63's later.

[Kent K.]

Re: C2 Exhaust Pipe Heat Shields

Mike ---- I believe, without absolute proof, that my '67 327ci/300hp exhaust heat shields are original to the car. How may I help? Would you like photos or ... ?
Kent #6201

[Gary B.]

I have my original '66 shields

Micheal,

I have what I think are the original shields for my '66 L79. Do you want photos? I'll have to try and remember where I stored them.

Gary

[Alan Drake]

Re: NOS shield and pn changes

Micheal,
Will send picture of NOS shield, pn 3851673, with GM IBM card still on it and other sticker with pn also.

Here's some more info;
63/64 AIM page D161 2" pipe calls for 3828281-2 shield L-R

page D300 21/2" calls for 3851673-4 shield L-R NPC-32

also see note on 7-2-63, was 3828285-6
Can somebody look at 65,66,&67 AIM to see what's there??

Now on to the Part Catalog
2" pipe;

3828281 L* 3864178 R
2 1/2" pipe;

3851673 L* 3864180 R

* number called for in AIM

Now Dr Rebuild has some nice pictures and calls for
63-64 and 65-67 for 2" pipes
63 T, 64-65 U, and 66-67 V for 2 1/2" pipes.

[James W.]

Re: C2 Exhaust Pipe Heat Shields

Michael,

I have an original pair off of an original '66 427/390, 4-speed equipped car. I can take pictures of them and send to you or send you the actual shields. What would you like???

Regardds,

James West
Omaha, NE.

[Michael H.]

New Email For This Topic

Thanks everyone. I just created a new email address/account just for this topic. We can send pic's there and I will post on the board. It was the easiest way I could think of to do this. Here's the address; heatshieldsurvey@yahoo.com . Try to limit the size to 640x480 if possible, or I can reduce for posting. Large pic's will overload the yahoo mail.

Also, if possible, give OL dimensions, model year and any other info that may be important.

I think this may be a great way to gather info on this, as long as we can get enough original samples.

The only year that I have well documented is the 2.5" for 63. I believe some changes occured near, or at, the end of the 63 run. Will be nice to get this sorted out. Thanks,

Michael

[Michael H.]

Original 63 Shields

Here's a used set from a mid production 63. Part numbers would be 3828281-282. Correct for 2 1/2" pipes and measure roughly 15" in length. I believe this style and part number continued to near the end of the 63 MY production. This would be the longest shields of the C2 run.

[George C.]

Re: Original 63 Shields

Michael,
Since I think I may have started this, let my offer what the 65 AIM says.
LH 3828281, RH 38264178
Since I don't have originals shields, the photos of my repros probabaly won't help, but let me know if you want them.

Thanks,

George

[Michael H.]

Re: Original 63 Shields

George,

Here's what I've found so far.

The original 63 part numbers listed in the AIM and a 1963 printing of the parts book were 3828281-282 for the 2" system and 3828285-286 for the 2 1/2" system. These numbers appear to have run the entire model year.

The 3828285-286 shields for the 2 1/2" system were replaced, at least in service, with 3851673-674 on 1-64. (this change may have occured earlier on the assy line, in fact may have occured at SOP of the 64 model, but I don't have a 64 AIM here to check)

I see no other changes for the 2 1/2" shields for the remainder of the C2 series. The same part numbers are listed in a 1969 printing of the parts book.

So, at least according to printed material, there was no difference between 64 and 67 for the 2 1/2" shields. That doesn't mean there weren't some design changes or modifications that occured either at the source or at the St. Louis plant. (unlikely) If we're seeing different designs, I would suspect these changes are happening at the vendor.

The shield for 63 was roughly 2 1/2" longer than the 64-67 shield and there may have been some clearance problem with this length. The rear 3" of EVERY original 63 shield that I've ever seen, including the set I have here, is bent down almost to the point of touching the exhaust pipe. It appears this "bend" was an assembly line patch until the new shorter shield showed up for the 64 model.I suspect this is the reason why the length was reduced from 15" to 12 1/2" for 64-67.

I have to guess that any other modifications that occured during the 64-67 run were also done "off print" and that's why we see no change in the part number. We'll have to rely on input from owners of original cars for info to document these changes. The parts book is quite limited as far as revealing what actually happened to these parts along the way.

Alan Drake sent a pic of an NOS 3851673 LH shield for 2 1/2" on 64-67 and it looks quite a bit different than a reproduction. The bend, or dip, in the center is almost non existant on his NOS shield but the bend in the reproduction looks just like the 63 style. I'll post a pic later.

For the 2" shields, they're easy. Only one change occured throughout the C2 run. The RH shield, 3828282, was replaced with a 3864178 some time during the 65 run. (I didn't look up the exact time of change) I don't know why the change though.

[Gerard F.]

Original late 67 Sheilds

Michael,

These are original from a late 6/29/67 base engine convertible. The 67 AIM shows 3851673 LH and 3864180 RH.


The LH one is about 13" long and the RH is only about 10". There was a thread about this last September about the long and short one. I think it was resolved that the short one was probably at the end of a sheild rolling and is missing the extension. There is no evidence that the extension may have broken off.

I'll see if I can find that thread and post a link.

There was hardly any bow in these, like the bow in the repro that George posted.
These were taken off for the first time, last year with the original front pipes from my 67. They fit pretty well with the repro front pipes.

Jerry Fuccillo
#42179

[Gerard F.]

Here's that thread on the Exhaust Shields

https://www.ncrs.org/forum/archive23.cgi?review=195502

[Michael H.]

Re: Original late 67 Sheilds

Jerry,

I've learned a bit more since my last post. Seems I was only half correct on the 64-67 era. I believe the 63-64 numbers that I posted earlier are correct and the left side for 64-67 is correct also. However, there was a change for SOP of 65 for the right side shield that continued till the end of 67 production. I don't have accurate descriptions for any of the 64-67 shields but here are the part numbers and years of application. All are for the 2 1/2" system. (2" coming soon) It's possible that some of the following number changes did not occur exactly at start of production but I'm pretty sure it happened very near to that.

63 left 3828285
63 right 3828286

64 left 3851673
64 right 3851674

65-67 left 3851673
65-67 right 3864180

Also, I agree on the fact that there was only a slight bow in the center of the 64-67 parts, as opposed to the deep bow for the 63 only part. The pic of Alan Drakes NOS 3851673 64-67 left side shows almost no bow at all. However, a pair of reproduction shields that I have does have the same deep bend, just like 63. I believe the reproduction is incorrect. I'll post Alan's pic later.

Also, the necked down, or reduced section, seems to be on the wrong end of the reproduction but not 100% sure on that yet.

At least we have the part numbers sorted out now. From here we can get actual physical descriptions for each part number.

I'm wondering if the short 10" right side was the change for 65-67?

[Michael H.]

NOS 3851673

Here's the Alan Drake NOS 3851673 shield. Correct for the left side of 64-67 w/2.5" pipes. Note that there is almost no bend, or swayback, as seen on some reproduction shields. I'm beginning to think that the deep bend was for the 63 only shields. I think I may know why this is. Isn't an original 63 pipe shaped quite differently than a 64 in the area where the shield is attached? Could this be the reason for the deep bend in a 63 shield, but not the 64-67?

[Michael H.]

Re: C2 Exhaust Pipe Heat Shields

James,

Pic's of the shields would be great. That would be much better than sending the actual parts as it may take many years, possibly decades, to thoroughly examine each piece. The shields are missing on my 66 and it may require actual prolonged road testing to properly evaluate and research these parts. Thanks.

Regards,

Michael

[Alan Drake]

Re: Did you mean 3864178 and . .

I think the pn is 3864178 as opposed to 38 2 64178 - yes ??
Also, what page in 65AIM is it from and is something also listed for the small motors with 2" pipes? Maybe 65 on only had 2 1/2" pipes, I do not know.
Thanks George, So who stared this!
Have a good day.
Alan